A special forces unit stormed an apartment and killed four suspects after they refused to surrender and opened fire, the KNB said in a statement. No casualties were reported among civilians or security forces.
Another man described as "the terrorists` accomplice" opened fire on police in the street, lightly wounding two, and was killed in return fire, the statement said. KNB said security forces were looking for other suspects still at large.
Authorities have not identified the group responsible for attacks on a national guard base and firearms shops in the city of Aktobe, in which at least 20 died on Sunday.
But Kazakh President Nursultan Nazarbayev on Friday called them Salafists, the followers of an ultra-conservative school of Islam.
Nazarbayev said on Wednesday the attackers had received instructions from abroad and were adherents of a pseudo-religious movement, but did not identify it.
ISLAMIC STATE LINK
One of the men blamed by authorities for the attack, the deadliest since the country became independent of the Soviet Union in 1991, had posted a video online sympathetic to Islamic State.
A message issued on May 21, purporting to come from a spokesman for Islamic State, called on followers abroad to launch attacks during the Islamic holy month of Ramadan, which began in early June.
A Russian version of the message can be found on social network Vkontakte, popular in the former Soviet Union and used by several people who were on the list of Aktobe suspects leaked to Kazakh media.
"Such groups (of Islamic State supporters) probably exist everywhere but ours, the Aktobe one, were among the first to react to this fatwa," said Astana-based religion researcher Asylbek Izbairov.
"Perhaps this was due to their links to Kazakh militants who have joined the Islamic State and traveled there."
An estimated 300 Kazakhs had left the country to join the militant group based in Syria and Iraq, half of them potential fighters and the other half their family members, Galym Shoikin, head of religious issues committee at Kazakhstan`s culture ministry, told reporters on Friday.
Shoikin also said there were about 15,000 Salafists in the predominantly Muslim but secular Central Asian nation of 18 million.
Kazakh forces kill five suspected of links to Islamist attack
12 June 2016
Read: 938
Kazakh security forces killed five people on Friday who were suspected of being Islamist militants linked to deadly attacks this week, the National Security Committee (KNB) said.
